Question Bank Cardiology – 2015
Questions #’s
1 – 127: Simple multiple choice questions
128 – 142: K-Type Questions
143 – 157: Vignette multiple choice questions with answers
1. A derivative of the intra-embryonic coelom
A. foregut
B. allantois
C. midgut
D. pericardial cavity
E. hindgut
2. Paired heart tubes are derived from
A. ectoderm
B. endoderm
C. neural crest
D. notochord
E. mesoderm
3. Paired heart tubes are derived from
A. paraxial mesoderm
B. intermediate mesoderm
C. cardiogenic mesoderm
D. somatic mesoderm
E. splanchnic mesoderm
1
4. The parietal pericardium is derived from
A. paraxial mesoderm
B. intermediate mesoderm
C. head mesenchyme
D. lateral plate somatic mesoderm
E. lateral plate splanchnic mesoderm
5. The visceral pericardium is derived from
A. paraxial mesoderm
B. intermediate mesoderm
C. head mesenchyme
D. lateral plate somatic mesoderm
E. lateral plate splanchnic mesoderm
6. Lymphatic vessels are derived from
A. surface ectoderm
B. endoderm
C. neural crest
D. neural ectoderm
E. mesoderm
7. Lymphatic vessels are derived from
A. lateral plate mesoderm
B. somitic mesoderm
C. mesenchyme
D. intermediate mesoderm
E. all of the above
2
8. Blood vessels are derived from
A. surface ectoderm
B. endoderm
C. neural crest
D. neural ectoderm
E. mesoderm
9. Incomplete fusion of the endocardial cushions is usually associated with which of the following types
of atrial septal defects ?
A. primum
B. secundum
C. probe patent
D. common atrium
E. sinus venosus
10. The fetal left atrium is mainly derived from the:
A. sinus venosus
B. right pulmonary vein
C. primitive pulmonary vein
D. primitive atrium
E. sinus venarum
11. The most common type of defect of the cardiac septa is a
A. muscular ventricular septal defect
B. primum atrial septal defect
C. secundum atrial septal defect
D. sinus venosus atrial septal defect
E. membranous ventricular septal defect
3
12. Closure of the foramen primum results from the fusion of the
A. septum primum and the septum secundum
B. septum primum and the endocardial cushions
C. septum secundum and the septum spurium
D. septum secundum and the endocardial cushions
E. septum primum and the right sinoatrial valve
13. The fetal right atrium is mainly derived from the
A. primitive pulmonary vein
B. primitive atrium
C. sinus venarum
D. sinus venosus
E. right pulmonary vein
14. The cardiovascular system reaches a functional state at the end of the _____________ week.
A. first
B. second
C. third
D. fourth
E. fifth
15. Incomplete fusion of the endocardial cushions is usually associated with which of the following types
of atrial septal defects ?
A. secundum
B. probe patent
C. common atrium
D. primum
E. sinus venosus
4
16. The fetal left atrium is mainly derived from the:
A. sinus venosus
B. right pulmonary vein
C. primitive atrium
D. sinus venarum
E. primitive pulmonary veins
17. The most common type of defect of the cardiac septa is
A. membranous ventricular septal defect
B. muscular ventricular septal defect
C. primum atrial septal defect
D. secundum atrial septal defect
E. sinus venosus atrial septal defect
18. Closure of the foramen primum results from the fusion of the
A. septum primum and the septum secundum
B. septum secundum and the septum spurium
C. septum primum and the endocardial cushions
D. septum secundum and the endocardial cushions
E. septum primum and the right sinoatrial valve
19. The fetal right atrium is mainly derived from the
A. primitive pulmonary vein
B. sinus venosus
C. primitive atrium
D. sinus venarum
E. right pulmonary vein
5
20. The most common congenital malformation of the heart and great vessels associated with the
congenital rubella syndrome is
A. coarctation of the aorta
B. tetralogy of Fallot
C. patent ductus arteriosus
D. atrial septal defect
E. ventricular septal defect
21. The 3rd pair of aortic arches gives rise to which of the following arteries ?
A. external carotid
B. common carotid
C. superficial temporal
D. laryngeal
E. subclavian
22. The cardiovascular system reaches a functional state at the end of the _____________ week.
A. second
B. third
C. fourth
D. fifth
E. sixth
23. Incomplete fusion of the endocardial cushions is usually associated with which of the following types
of atrial septal defects ?
A. probe patent
B. secundum
C. primum
D. common atrium
E. sinus venosus
6
24. The fetal left atrium is mainly derived from the:
A. sinus venosus
B. right pulmonary vein
C. primitive pulmonary vein
D. primitive atrium
E. sinus venarum
25. The most common type of defect of the cardiac septa is
A. muscular ventricular septal defect
B. primum atrial septal defect
C. secundum atrial septal defect
D. sinus venosus atrial septal defect
E. membranous ventricular septal defect
26. Closure of the foramen primum results from the fusion of the
A. septum primum and the septum secundum
B. septum primum and the endocardial cushions
C. septum secundum and the septum spurium
D. septum secundum and the endocardial cushions
E. septum primum and the right sinoatrial valve
27. The fetal right atrium is mainly derived from the
A. primitive pulmonary vein
B. primitive atrium
C. sinus venarum
D. sinus venosus
E. right pulmonary vein
7
28. The most common congenital malformation of the heart and great vessels associated with the
congenital rubella syndrome is
A. coarctation of the aorta
B. tetralogy of Fallot
C. patent ductus arteriosus
D. atrial septal defect
E. ventricular septal defect
30. In the foetal circulatory system mixing of oxygenated and deoxygenated blood occurs in
all of the following, EXCEPT
A.
B.
C.
D.
E.
ductus arteriosus
inferior vena cava
left atrium
liver
lungs
31. Which of the following statements is NOT correct
A. the sinus venosus serves as the pacemaker of the heart of the young embryo
B. the septum primum completely divides the developing atrium into right and left
compartments
C. in the adult heart, the sinus venous is represented by the sino-atrial node
D. the two endocardial cushions divide the atrioventricular (AV) canal into the
right tricuspid and left bicuspid (mitral) canals.
E. the fusion of the right superior truncus swelling with the left inferior truncus
swelling forms the aorticopulmonary septum
8
32. Which of the following statements is NOT correct
A. the trabeculated portion of the right atrium is derived from the right horn of the
sinus venosus
B. the coronary sinus is derived from the left horn of the sinus venosus
C. the epicardium is synonymous with the visceral layer of pericardium (visceral
pericardium)
D. at the fourth week, each horn of the sinus venosus receives blood from the vitelline
(omphalomesenteric) vein, the umbilical vein, and the common cardinal vein
E. the valve of the inferior vena cava is derived from the right venous valve of the right
horn of the sinus venosus
33. Which of the following is NOT part of the tertralogy of Fallot?
A.
B.
C.
D.
E.
Pulmonary infundibular stenosis
interventricular septal defect
aorta arising from both ventricular cavities (dextroposition of the aorta)
hypertrophy of the right ventricular wall
interatrial septal defect
34. Which of the following statements is NOT correct
A. the heart and great vessels originate from mesoderm
B. the ostium secundum defect may be due to excessive resorption of the
septum primum
C. the ostium secundum defect may be due to inadequate development of the
coronary sinus
D. failure of the truncoconal septum to follow its normal spiral course can lead to
transposition of the great vessles
E. the septum primum is located to the left of the septum secundum (in the anatomical
position)
9
35. Which of the following statements is NOT correct
A. the third aortic arch forms the common carotid artery and the first part of the
internal carotid artery
B. on the left, the fourth aortic arch forms part of the arch of the aorta between the
left common carotid artery and the left subclavian artery
C. on the right, the fourth aortic arch forms the most proximal segment of the right
subclavian artery
D. on the left side, the sixth aortic arch forms the ductus arteriosus
E. the maxillary artery is formed from the second aortic arch
36. Which of the following statements is NOT correct
A. the atrioventricular node and atrioventricular bundle (of His) are derived from cells
in the left wall of the sinus vensous and from cells in the atrioventricular canal
B. probe patency of the foramen ovale does not permit shunting of blood from the
right atrium to the left atrium in the neonate
C. the ostium primum lies between the septum primum and the endocardial cushions
D. the muscular portion of the interventricular septum is derived from the tissue of the
endocardial cushions
E. most interventricular septal defects involve the membranous part of the interventricular
septum
37. Tetralogy of Fallot includes each of the following EXCEPT
A. overriding aorta
B. right ventricular out flow obstruction
C. interventricular septal defect
D. transposition of the pulmonary artery
E. right ventricular hypertrophy
10
38. The jet lesion of aortic insufficeincy is characteristically
A.
B.
C.
D.
E.
in the aortic root
at the base of the ventricular septum
both
neither
none of the above
39. The sino-atrial node, the atrioventricular node, and the Purkinje fibers of the heart develop
from
A. neurons from the spinal cord which migrate into the mesenchyme of the
developing myocardium
B. cells from the neural crest which migrate into the developing myocardium
C. connective tissue fibers which are intrinsically capable of generating electrical
activity
D. ectodermal cells which are intrinsically capable of generating electrical activity
E. mesodermal cells of the myocardium which become specialized conducting cardiac
muscle cells
40. In the uncomplicated patent ductus arteriosus, as might be seen in an infant 6 months of age,
blood flows from the aorta to the
A. pulmonary vein
B. pulmonary artery
C. right ventricle
D. right atrium
E. left atrium
41. In the foetal circulatory system mixing of oxygenated and deoxygenated blood occurs in
all but one of the following
A.
B.
C.
D.
E.
ductus arteriosus
inferior vena cave
left atrium
liver
lungs
11
42. The tunica media of vessels of all types develops from the layer of the trilaminar embryo
known as
A.
B.
C.
D.
E.
scleroderm
entoderm
mesoderm
ectoderm
neural crest
43. Arteries and veins of all caliber appear first in the embryo as typical
A.
B.
C.
D.
E.
arteries
lymphatic ducts
capillaries
veins
vasa vasorum
44. The tunica media of vessels of all types develops from the layer of the trilaminar embryo
known as
A.
B.
C.
D.
E.
mesoderm
entoderm
scleroderm
ectoderm
neural crest
45. In the embryo, after the closed vascular system develops, new vessels always form
A. by "budding" from pre-existing vessels
B. by the formation of mesenchymal "tubes" which connect to pre-existing channels.
C. by the invagination of ectodermal sprouts which connect to larger vessels
D. by the evagination of ectodermal tubes which become arterial for the most part
E. from the vacuolization of neural crest cell cylinders which form the model for new
vessels
12
46. All of the following are dilatations formed in the primitive heart tube as the first indication of
chamber formation except the
A.
B.
C.
D.
E.
sinus venosus
bulbus cordis
dorsal aortae
ventricle
aortic sac
47. The venous end of the primitive heart tube receives blood from all of the following,
EXCEPT
A. vitelline arteries
B. vitelline veins
C. left umbilical vein
D. common cardinal vessels
E. right umbilical vein
48. The pulmonary trunk and aorta are formed by division of the truncus arteriosus by the
formation of the
A. septum primum
B. septum secundum
C. ventricular septum
D. aorticopulmonary septum
E. crista terminalis
13
49. The sino-atrial node, the atrioventricular node, and the Purkinje fibers of the heart develop
from
A. neurons from the spinal cord which migrate into the mesenchyme of the developing
myocardium
B. cells from the neural crest which migrate into the developing myocardium
C. connective tissue fibers which are intrinsically capable of generating electrical
activity
D. ectodermal cells which are intrinsically capable of generating electrical activity
E. mesodermal cells of the myocardium which become specialized conducting cardiac
muscle cells
50. The ductus arteriosus is a remnant of the left
A.
B.
C.
D.
E.
sixth aortic arch
fifth aortic arch
second aortic arch
first aortic arch
third aortic arch
51. The pulmonary arteries are derivatives of the
A.
B.
C.
D.
E.
first aortic arch
second aortic arch
fourth aortic arch
fifth aortic arch
sixth aortic arch
52. The third aortic arch arteries become on both sides the
A. pulmonary arteries
B. paired dorsal aorta
C. arch of the aorta
D. common carotid arteries
E. brachiocephalic arteries
14
53. The common iliac arteries are derived from enlargements of
A.
B.
C.
D.
E.
a portion of the seventh cervical intersegmental arteries
the fifth lumbar intersegmental arteries
the middle sacral artery
the intercostal arteries
the umbilical arteries
54. The fetal left umbilical vein has an adult intrahepatic remnant known as the
A.
B.
C.
D.
E.
ligaments teres (hepatic)
ligamentum venosum
ligamentum arteriosum
inferior vena cave
falciform ligament
55. Congenital heart disease is the most common cardiac condition in childhood and most
frequently results from
A.
B.
C.
D.
E.
maternal medications
mutant genes
rubella virus
fetal distress
genetic and environmental factors
56. The most common type of defect of the cardiac septa is
A. secundum type ASD
B. muscular type ASD
C. primum type ASD
D. membranous type VSD
E. sinus venous
15
57. The fetal left atrium is mainly derived from the
A.
B.
C.
D.
E.
primitive pulmonary vein
primitive atrium
right pulmonary vein
sinus venarum
sinus venosus
58. The fetal right atrium is mainly derived from the
A.
B.
C.
D.
E.
primitive pulmonary vein
primitive atrium
right pulmonary vein
sinus venarum
sinus venosus
59. Incomplete fusion of the endocardial cushions is usually associated with which of the
following types of atrial septal defect (ASD)?
A.
B.
C.
D.
E.
secundum type ASD
primum type ASD
common atrium
probe patent ASD
sinus venous type ASD
60. The most common type of defect of the cardiac septa is
A. secundum atrial septal defect
B. muscular ventricular septal defect
C. primum atrial septal defect
D. membranous ventricular septal defect
E. sinus venosus atrial septal defect
16
61. Closure of the foramen primum results from the fusion of the
A. septum primum and the septum secundum
B. septum secundum and the septum spurium
C. septum primum and the endocardial cushions
D. septum secundum and the endocardial cushions
E. septum primum and the right sinoatrial valve
62. The most common congenital malformation of the heart and great vessels associated with the
congenital rubella syndrome is
A. coarctation of the aorta
B. tetralogy of Fallot
C. patent ductus arteriosus
D. atrial septal defect
E. ventricular septal defect
63. Capillaries, like all vessels, develop from embryonic
A. endoderm
B. mesoderm
C. ectoderm
D. neural crest
E. notochord
64. Incomplete fusion of the endocardial cushions is usually associated with which of the following types
of atrial septal defects ?
A. secundum
B. primum
C. common atrium
D. probe patent primum
E. sinus venosus
17
65. Which of the following mesodermal populations gives rise to the cell mass from which the
myocardium develops ?
A. somatopleuric mesoderm
B. hypomeric mesoderm
C. epimeric mesoderm
D. splanchnopleuric mesoderm
E. prechordal plate mesoderm
66. Which of the following combinations correctly pairs a fetal atrial septum with the opening(s) found
in it ?
Septum
A. Septum Primum
B. Septum Secundum
C. Septum Primum
D. Septum Secundum
E. Septum Primum
Openings
Foramen Ovale
Ostium primum and ostium secundum
Ostium primum and ostium secundum
Ostium secundum
Ostium secundum and foramen ovale
67. Which of the following conditions would be observed in a case of complete dextrocardia ?
A. The apex of the heart pointing toward the individual's left side.
B. The pulmonary trunk draining the ventricle on the left side
C. The bicuspid valve positioned between the atrium on the left side and the
ventricle on the left side.
D. The septum secundum forming part of the wall of the atrial chamber on the
right side.
E. The ostium secundum located in the septum forming part of the wall of the
atrial chamber on the left side.
18
68. During the remodeling of the inflow end of the heart, which of the following embryonic structures
gives rise to the coronary sinus ?
A. Left horn of the sinus venosus
B. Right anterior cardinal vein
C. Left vitelline vein
D. Right horn of the sinus venosus
E. Left posterior cardinal vein
69. The definitive right atrium (excluding the right auricle) arise from the
A. Right pulmonary vein
B. Left pulmonary vein
C. Right vitelline vein
D. Right horn of the sinus venosus
E. Right anterior cardinal vein
70. Typically, the abnormal flow of blood in a congenital atrial septal defect results from overlapping of
the
A. Ostium primum and ostium secundum
B. Septum primum and septum secundum
C. Foramen ovale and septum primum
D. Septium primum and septum spurium
E. Ostium secundum and foramen ovale
71. The tetralogy of Fallot is an association of anomalies that arises through a pathogenic cascade of
malformations in the heart. Which of the following anomalies would be considered to be the final defect
in this pathogenic cascade ?
A. Constricted subpulmonary orifice.
B. Pulmonary stenosis
C. Rightward displacement of the aorta (overriding aorta)
D. Ventricular septal defect
E. Enlarged right ventricle
19
72. During embryonic development, blood vessel formation by the process of vasculogenesis (in situ
vesicle formation and fusion) begins first in which of the following embryonic tissues ?
A. Extraembryonic mesoderm of the primary yolk sac
B. Extraembryonic endoderm of the definitive yolk sac
C. Intraembryonic splanchnopleuric mesoderm
D. Prechordal plate mesoderm
E. Neural crest ectomesenchyme
73. In humans, the left fourth aortic arch gives rise to a portion of which of the following structures ?
A. Ductus arteriosus
B. Arch of the aorta
C. Left subclavian artery
D. Left common carotid artery
E. Left external carotid artery
74. The right recurrent laryngeal nerve loops under a derivative of which of the following aortic arches ?
A. Second aortic arch
B. Third aortic arch
C. Fourth aortic arch
D. Fifth aortic arch
E. Sixth aortic arch
75. The definitive renal arteries arise directly from
A. Vessels that sprout from the aorta at the pelvic level where the kidneys
(metanephroi) originate
B. Vessels that sprout from the aorta at the definitive, lumbar level of the
kidneys (metanephroi)
C. Vessels that initially sprout from the aorta to vascularize the suprarenal glands
D. Arteries of the vitelline system
E. Intersegmental arteries in the lumbar region
20
76. Which of the following embryonic vessels gives rise to the ductus venosus ?
A. Right umbilical vein
B. Left umbilical vein
C. Right and left umbilical veins
D. Right and left vitelline veins
E. Right and left supracardinal veins
77. The definitive thoracic duct of the lymphatic system is derived from which of the following
combinations of embryonic lymphatic vessels ?
A. The caudal segment of the right lymphatic duct and the cranial segment of
the left lymphatic duct.
B. The caudal and cranial segments of the right lymphatic duct
C. The caudal segment of the left duct and the cranial segment of the right duct
D. The caudal and cranial segments of the left duct
E. The caudal and cranial segments of the right and left ducts
78. In a normal fetus shortly before birth, which of the following vessels or heart chambers would
contain the most highly oxygenated blood ?
A. Right ventricle of the heart
B. Ductus arteriosus
C. Umbilical arteries
D. Pulmonary trunk
E. Common carotid arteries
79. In a particular newborn infant, a substantial volume of blood takes the following route from the left
ventricle to the lower limbs: ascending aorta to brachiocephalic artery to right subclavian artery to right
internal thoracic artery to right anterior intercostal artery to right posterior intercostal artery to
descending aorta. Which of the following conditions does this infant probably have ?
A. Double aortic arch
B. Coarctation of the aorta proximal to the ductus arteriosus
C. Coarctation of the aorta distal to the ductus arteriosus
D. Situs inversus
E. Abnormal right subclavian artery passing posterior to the esophagus and
trachea
21
80. The right recurrent laryngeal nerve loops under a derivative of which of the following aortic arches ?
A. First aortic arch
B. Second aortic arch
C. Third aortic arch
D. Fourth aortic arch
E. Fifth aortic arch
81. A female infant with congestive heart failure and a continuous systolic and diastolic murmur was
diagnosed as having a patent ductus arteriosus. Which of the following statements is correct?
A. The ductus arteriosus is a remnant of the left fourth aortic arch.
B. The ductus arteriosus is closed during fetal development.
C. The ductus arteriosus shunts blood from the umbilical vein to the inferior vena
cava.
D. The ductus arteriosus closes just before birth.
E. In the fetus, most of the blood from the pulmonary trunk flows into the
aorta.
82. The ductus arteriosus is derived from the
A. left fourth aortic arch
B. right fourth aortic arch
C. left fifth aortic arch
D. right fifth aortic arch
E. left sixth aortic arch
83. The arch of the aorta is derived from the
A. left fourth aortic arch
B. right fourth aortic arch
C. left fifth aortic arch
D. right fifth aortic arch
E. left sixth aortic arch
22
84. Normally the ductus arteriosus closes/constricts
A. during the fetal period
B. just before birth
C. at birth
D. during puberty
E. it doesn't constrict
85. On routine examination a loud murmur was detected at the lower left sternal border of an infant
who has failed to thrive and has poor weight. A diagnosis of VSD (ventricular septal defect) was made,
and subsequently, the absence of the membranous part of the septum was confirmed by twodimensional echocardiography. Membranous VSD __________________ .
A. arises from the failure of subendocardial tissue of the endocardial
cushions to fuse with the aorticopulmonary septum and muscular part
of the interventricular septum.
B. results from excessive resorption of myocardial tissue.
C. causes shunting of blood from the right ventricle to the left ventricle
D. is found only in association with an ASD (atrial septal defect).
E. is a rare condition and the less common type of VSD.
86. In membranous VSD there is a shunting of blood
A. from the left atrium to the right atrium
B. from the left ventricle to the right ventricle
C. from the right ventricle to the right atrium
D. from the left ventricle to the left atrium
E. from the left ventricle to the right atrium
87. Transposition of the great (arteries) vessels was diagnosed in a male infant with obvious cyanosis
and mild tachypnea. This condition results from which of the following?
A. abnormal resorption of the septum primum
B. failure of the endocardial cushions to fuse
C. faulty partitioning of the bulbous cordis and truncus arteriosus
D. involution of the ductus arteriosus
E. abnormal transformation of the sixth aortic arches
23
88. The right auricle of the heart is derived from the
A. primitive pulmonary vein
B. sinus venosus
C. right pulmonary vein
D. sinus venarum
E. primitive atrium
89. Congenital heart disease most frequently results from
A. maternal medications
B. rubella virus
C. mutant genes
D. fetal distress
E. genetic and environmental factors
90. The most common congential anomaly of the heart and great vessels associated with the congenital
rubella syndrome is
A. coarctation of the aorta
B. tetralogy of Fallot
C. patent ductus arteriosus
D. atrial septal defect
E. ventricular septal defect
91. During embryonic development (within the embryo proper), blood vessel formation by the process
of vasculogenesis (in situ vesicle formation and fusion) begins first in which of the following embryonic
tissues?
A. extraembryonic mesoderm of the primary yolk sac
B. extraembryonic endoderm of the definitive yolk sac
C. intraembryonic splanchnopleuric mesoderm
D. prechordal plate mesoderm
E. neural crest ectomesenchyme
24
92. During embryonic development, blood vessel formation by the process of blood island formation
begins first in which of the following tissues
A. extraembryonic endoderm of the primary yolk sac
B. extraembryonic splanchnic mesoderm of the definitive yolk sac
C. intraembryonic splanchnic mesoderm of the definitive yolk sac
D. prechordal plate mesoderm
E. neural crest
93. In humans the left fourth aortic arch gives rise to a portion of which of the following structures?
A. ductus arteriosus
B. arch of the aorta
C. left subclavian artery
D. left common carotid artery
E. left external carotid artery
94. The ductus arteriosus has an adult remnant known as the
A. ligamentum teres
B. ligamentum venosus
C. ligamentum arteriosum
D. inferior vena cava
E. falciform ligament
95. All of the following statements are true with respect to development of the cardiovascular system
EXCEPT
A. Angioblasts (mesenchyme cells) condense to from blood islands in the
extraembryonic mesoderm of the definitive yolk sac
B. Angioblasts in the center of the blood islands form nucleated blood cells and
plasma.
C. Blood formation begins in week 5 in the embryonic yolk sac, at week 6 lin the
liver, at 2.5 months in the spleen, and 2-3 months in the bone marrow.
D. Blood formation normally continues in the liver and spleen after birth.
E. Fetal hemaglobin predominates at birth.
25
96. Vitelline vessels form
A. at the cranial end of the embryo
B. at the caudal end of the embryo
C. in the connecting stalk
D. in the chorion
E. on the yolk sac
97. The anterior cardinal vein forms
A. at the cranial end of the embryo
B. at the caudal end of the embryo
C. in the connecting stalk
D. in the chorion
E. on the yolk sac
98. The posterior cardinal vein forms
A. at the cranial end of the embryo
B. at the caudal end of the embryo
C. in the connecting stalk
D. in the chorion
E. on the yolk sac
99. Umbilical vessels form
A. at the cranial end of the embryo
B. at the caudal end of the embryo
C. in the connecting stalk
D. in the chorion
E. on the yolk sac
26
100. Chorionic vessels form
A. at the cranial end of the embryo
B. at the caudal end of the embryo
C. in the connecting stalk
D. in the chorion
E. on the yolk sac
101. Which of the following appear as a single vessel during early embryogenesis?
A. vitelline
B. cardinal
C. umbilical
D. branchial aorta
E. none of the above
102. Which vessels carry the highest oxygenated blood?
A. aorta
B. umbilical arteries
C. vitelline veins
D. umbilical veins
E. cardinal veins
103. All of the following are true with respect to vessel formation EXCEPT
A. Blood vessels arise from the aortic sac to supply each branchial arch.
B. The fifth aortic arch arteries persist as the subclavian arteries.
C. The left fourth arch artery persists as a part of the arch of the aorta.
D. The right sixth aortic arch becomes the right pulmonary artery.
E. The left sixth aortic arch becomes the left pulmonary artery and the ductus arteriosus.
27
104. All of the following statements are true EXCEPT
A. Two vitelline veins pass from the yolk sac to the sinous venosus of the heart.
B. Two vitelline veins pass through the mesenchyme of the septum transversum.
C. The liver forms in the septum transversum.
D. The liver intermingles with the vitelline veins and a network of blood vessels are formed.
E. Hepatic veins form from the remains of the left vitelline veins.
105. All of the following statements are true EXCEPT
A. Two umbilical veins pass through the septum transversum from the placenta to
the sinous venosus.
B. As the liver forms, a connecting branch develops between each umbilical vein
and the vitelline vein network.
C. Even though these new (umbilical-vitelline) channels have formed, the
umbilical veins still retain direct connections to the sinous venosus.
D. Blood from the left umbilical vein becomes the predominant flow from the
placenta.
E. The left umbilical vein crosses the liver to the inferior vena cava through the
ductus venosus.
106. All of the following statements are true EXCEPT
A. The portal veins forms from an anastomotic network of vitelline veins around
the duodenum.
B. The portion of the left vitelline vein nearest the liver disappears.
C. Vestige of the left umbilical vein can be recognized as the fibrous ligamentum
teres.
D. Vestige of the ductus venosus is the ligamentum venosum.
E. Two additional sets of veins develop near the cardinal veins: a ventral network
called the subcardinal veins and a dorsal network called the supracardinal veins.
107. The following is/are a derivative of the supracardinal veins:
A. renal veins
B. gonadal veins
C. suprarenal veins
D. iliac veins
E. hemiazygous vein
28
108. All of the following are true EXCEPT
A. The oblique vein of the heart develops from an oblique connecting vessel
between the two anterior cardinal veins.
B. The suprarenal vein develops from the subcardinal vein.
C. The hemiazygous vein and azygous vein are derivatives of the supracardinal
veins.
D. The iliac veins are derivatives of the caudal portion of the posterior cardinal
veins.
E. The gonadal veins develop from the supracardinal veins and anastomosis.
109. All the following are true with respect to early heart development EXCEPT
A. Paired endocardial heart tubes form from mesenchymal cardiogenic cords.
B. Surrounding splanchnic mesenchyme will later form the myocardium and
epicardium.
C. The endocarial heart tubes remain paired to form the right and left sides
of the heart.
D. The primitive heart is anchored at both ends: to the septum transversum
caudally and to the aortic sac and aortic arches cephalically.
E. The outflow tract is composed of the truncus arteriosus and the bulbus cordis.
110. The dilations of the embryonic heart tube consist of all of the following EXCEPT
A. the primitive ventricle
B. truncus arteriosus
C. the aortic sac
D. the sinous venosus
E. the primitive atrium
29
111. All the following are true with respect to heart development EXCEPT
A. During weeks 2-3 the single heart tube is divided into four chambers.
B. The right and left sides of the heart are separated from each other by the
endocardial cushions.
C. The endocardial cushions appear on the dorsal and ventral walls of the heart
tube in the midline, grow toward one another, and fuse.
D. Fusion of the endocardial cushions result in the right and left atrioventricular
canals.
E. Fusion of the endocardial cushions initiates the separation of the atria and
ventricles of the heart.
112. All the following are true with respect to heart development EXCEPT
A. Two atria form when the septum primum grows from the dorsal wall and fuses
with the endocardial cushion.
B. As the septum primum grows, the intervening gap between the wall and the
cushion is called the foramen primum.
C. The foramen secundum appears in the superior border of the septum primum.
D. The foramen primum allows blood to flow from the left atrium to the
right atrium.
E. Backflow of blood in the atria is prevented by the septum secundum which
grows from the ventral wall and tho the right of the septum primum.
113. All the following are true with respect to heart development EXCEPT
A. The embryonic atrium is identifiable in the adult as the auricle
B. The auricle is that region of the atrium with a smooth wall.
C. In the right atrium the smooth walls are tissues originating from the
incorporated right horn of the sinus venosus.
D. The smooth wall of the left atrium is derived from the incorporated pulmonry
veins.
E. The inferior border of the septum secundum is called the crista dividens.
30
114. All the following are true with respect to heart development EXCEPT
A. The muscular portion of the interventricular septum forms in the midline and
grows towards the endocardial cushion.
B. The interventricular foramen persists until week 7, allowing communication
between the two ventricles.
C. The interventricular foramen closes by the fusion of three membranes: the
interventricular septum, the bulbar ridge, and the aorticopulmonary
septum, forming the membranous part of the interventricular septum.
D. The smooth parts of the right and left ventricles are those regions of the bulbar
ridge and the aorticopulmonary septum.
E. The right ventricle is formed primarily from the primitive ventricle, while
the left ventricle forms from the bulbus cordis.
115. All the following are true with respect to heart development EXCEPT
A. The bulbus cordis and truncus arteriosus are separated longitudinally by
a straight septum.
B. The bulbus cordis and truncus arteriosus form the ascending aorta and
pulmonary trunk.
C. The sinoatrial node originally forms in the wall of the right horn of the sinus
venosus. When the right horn is incorporated into the right atrium, the
node is also incorporated.
D. The atrioventricular node and bundle form from cells in the atrioventricular
canal region and the sinus venosus.
E. The sinoatrial node, and the atrioventricular node and bundle become richly
innervated.
31
116. All the following are true with respect to heart development EXCEPT
A. As the bulboventricular loop forms, the primitive atrium is carried behind
(dorsal to) the primitive ventricle.
B. The sinous venosus attached to the primitive atrium has a left and right horn
with three vessels entering each horn.
C. The vessels entering each horn of the sinus venosus are the supracardinal,
subcardinal, and posterior cardinal veins.
D. As the two atria form, the right horn of the sinus venosus which has enlarged is
incorporated into the wall of the right atrium.
E. The embryonic atrium persists as the right auricle, the rough-walled appendage
of the atrium.
117. All the following are true with respect to heart development EXCEPT
A. The smaller left horn of the sinus venosus froms the coronary sinus.
B. The right anterior cardinal vein contributes to the inferior vena cava.
C. The right vitelline vein contributes to the inferior vene cava.
D. The common cardinal veins contribute to the superior vena cava.
E. The left common cardinal vein forms the oblique vein of the heart.
118. All the following are true with respect to heart development EXCEPT
A. All of the valves of the heart form differently.
B. Subendocardial tissue swellings form at the site of the future valves.
C. These swellings subsequently hollow out to form cusps.
D. The valves of the aorta and truncus arteriosus form as the spiral septum
separates the two vessels.
E. Originally four endocardial cushions arise, but two of the cushions are pinched
and divided in half as the vessels form resulting in two sets of tricuspid
valves.
32
119. How many shunts are there in the fetal cardiovascular system which cause blood to bypass the liver
and the lungs?
A. 1
B. 2
C. 3
D. 4
E. 5
120. All the following are true with respect to fetal vascular supply EXCEPT
A. The ductus venosus acts as a liver bypass to shunt blood to the heart.
B. Blood returning from the placental in the umbilical vein is deoxygenated.
C. As blood enters the fetus through the umbilical vein it is split into two halves.
D. Approximately half of the umbilical vein blood is directed through the portal
sinus to the portal vein and through the heptic sinusoids. The blood then
drains into the inferior vena cava.
E. The other half of the umbilical vein blood bypasses the liver by entering the
ductus venosus and passing directly into the inferior vena cava.
121. All the following are true with respect to fetal vascular supply EXCEPT
A. The foramen ovale acts to shunt blood to the inflated lungs.
B. In the inferior vena cava, deoxygenated blood from the lower limbs, abdomen,
and pelvis mixes with oxygenated umbilical vein blood and blood from
the hepatic sinusoids.
C. Upon entering the right atrium of the heart, most of the blood from the inferior
vena cava is directed through the foramen ovale by the inferior border of
the septum secundum (crista dividens).
D. After blood enters the left atrium, it mixes with a small amount of blood from
the uninflated lungs.
E. The blood in the left atrium then passes into the left ventricle and into the
ascending aorta to supply the heart, head, neck, and upper extremities.
33
122. All the following are true with respect to fetal vascular supply EXCEPT
A. A small amount of blood in the right atrium mixes with deeoxygenated blood
from the superior vena cava and coronary sinus.
B. This small amount of right atrial blood passes into the right ventricle and into
the pulmonary trunk.
C. Because of the high pulmonary resistance, most of this blood bypasses the
lungs and passes through the ductus arteriosus into the aorta.
D. Approximately half of blood passing through the ductus arteriosus supplies the
abdomen, pelvis, and lower limbs.
E. Approximately half of blood from the ductus arteriosus returns via the
two umbilical veins to the placenta and is deoxygenated.
123. All of the following are true with respect to vascular changes at birth EXCEPT
A. At birth, the lungs expand and pulmonary resistance is reduced.
B. Decreased pulmonary resistance means a greatly increased blood flow passes
through the pulmonary arteries to the lungs.
C. The ductus arteriosus then closes and will eventually form the fibrous
ligamentum arteriosus of the adult.
D. The ductus venosus can remain patent as a developmental anomaly.
E. Blood returning through the pulmonary veins into the right atrium causes
a decrease in pressure in the left atrium.
34
124. All of the following are true with respect to vascular changes at birth EXCEPT
A. Blood returning through the pulmonary veins into the left atrium causes an
increase in pressure in the left atrium.
B. Increased pressure in the left atrium causes the septum primum to be pressed
against the septum secundum.
C. The foramen ovale then remains functionally open.
D. In the adult, the site of the former septum primum is the floor of the fossa
ovalis.
E. In the adult, the site of the former inferior edge of the septum secundum (crista
dividens) is located at the limbus fossae ovalis (anulus ovalis).
125. All of the following are true with respect to vascular changes at birth EXCEPT
A. During postnatal development, most of the umbilical vessels within the infant
become ligamentous.
B. The umbilical vein forms the ligamentum teres.
C. Distally the umbilical arteries form the medial umbilical ligaments.
D. The ductus venosum forms the falciform ligament.
E. Proximally the umbilical arteries form the superior vesical arteries.
126. All of the following are true with respect to congenital malformations of the heart and great vessels
EXCEPT
A. High atrial septal defect is due to persistance of the foramen ovale.
B. Low atrial septal defect is due to persistance of the interventricular
foramen.
C. A persistant foramen ovale can be caused by underdevelopment of the septum
secundum.
D. A persistant foramen ovale can be caused by excessive resorption of the
septum primum.
E. A persistant foramen ovale can be caused by a combination of C & D.
35
127. All of the following are true with respect to congenital malformations of the heart and great vessels
EXCEPT
A. Interventricular septal defects are the least common congenital heart
defect.
B. Ventricular septal defects (VSD) are usually found in the membranous part of
the interventricular septum.
C. Anomalous formation of the aorticopulmonary septum can result in tetrology
of Fallot.
D. Tetrology of Fallot may include pulmonary valve stenosis and an overriding
aorta.
E. Tetrology of Fallot may include a ventricular septal defect and hypertrophy of
the right ventricle.
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K-Type Questions
128. Blood vessels eventually form in which of the following mesodermal tissues
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. extraembryonic mesoderm of the definitive yolk sac
2. prechordal plate mesoderm
3. intraembryonic splanchnopleuric mesoderm
4. neural crest ectomesenchyme
36
129. The adult inferior vena cava forms from the following primordia
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. A terminal portion from the right vitelline vein and hepatic vein and sinusoids.
2. A segment cranial to the renal segment which is derived from the right subcardinal vein.
3. A renal segment formed from the anastomosis of the subcardinal and supracardinal veins.
4. A segment caudal to the renal segment formed from the right supracardinal vein.
130. The foramen ovale consists of the following
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. septum secundum
2. septum primum
3. foramen secundum
4. forament primum
131. Vessels directly entering each horn of the sinus venosus include
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. common cardinal veins
2. supracardinal veins
3. vitelline veins
4. subcardinal veins
37
132. Vessels directly entering each horn of the sinus venosus include
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. supracardinal veins
2. vitelline veins
3. subcardinal veins
4. umbilical veins
133. Vessels directly entering each horn of the sinus venosus include
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1.supracardinal veins
2. anterior cardinal veins
3. subcardinal veins
4. common cardinal veins
134. Vessels directly entering each horn of the sinus venosus include
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. common cardinal veins
2. umbilical veins
3. vitelline veins
4. posterior cardinal veins
38
135. Which of the following are true with respect to heart development?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. The early ventricular wall is composed of three layers: an outer myoepicardial
mantel, a middle layer of cardiac jelly, and an inner layer of endothelial
tissue.
2. Ingrowths from the myoepicardial mantel spread into the cardiac jelly.
3. The endothelial tissue grows out and ensheathes the myoepicardial ingrowths
with epithelium.
4. The cardiac jelly disappears and the epithelial covered myoepicardial ingrowths
form the trabeculae carneae, papillary muscles, and the chordae tendineae.
136. Which of the following are shunts in the fetal cardiovascular system which cause blood to bypass
the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus venosus
2. foramen ovale
3. ductus arteriosus
4. ductus teres
39
137. Which of the following are shunts in the fetal cardiovascular system which cause blood to bypass
the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus venosus
2. foramen primum
3. ductus arteriosus
4. ductus teres
138. Which of the following are shunts in the fetal cardiovascular system which cause blood to bypass
the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus teres
2. ductus venosus
3. foramen primum
4. ductus arteriosus
139. Which of the following is/are shunts in the fetal cardiovascular system which cause blood to bypass
the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus teres
2. interventricular foramen
3. foramen primum
4. ductus arteriosus
40
140. Which of the following is/are shunts in the fetal cardiovascular system which cause blood to
bypass the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus teres
2. interventricular foramen
3. foramen primum
4. ductus venosus
141. Which of the following is/are shunts in the fetal cardiovascular system which cause blood to
bypass the liver and the lungs?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. ductus teres
2. interventricular foramen
3. foramen primum
4. foramen ovale
142. Which of the following is/are possible complications associated with Tetrology of Fallot?
A. If 1, 2, & 3 are correct
B. If 1 & 3 are correct
C. If 2 & 4 are correct
D. If only 4 is correct
E. If all are correct
1. pulmonary valve stenosis
2. an overriding aorta
3. a ventricular septal defect
4. hypertrophy of the right ventricle
41
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Vignette multiple choice questions with answers
143. How many shunts are there in the fetal cardiovascular system which cause blood to bypass the liver
and the lungs?
A. 1
B. 3
C. 5
D. 7
E. 9
Notes: Knowledge
There are three shunts in the fetal cardiovascular system: ductus venosus shunts blood through the liver
to the inferior vena cava, the foramen ovale connects the right atrium with the left atrium, and the
ductus arteriosus connects the pulmonary trunk with the aorta.
144. In the fetal circulatory system, which of the following vessels or organs would contain the most
highly oxygenated blood?
A.
B.
C.
D.
E.
Ascending aorta
Ductus arteriosus
Left atrium
Right ventricle
Umbilical vein
Notes: Analysis
The umbilical vein coming from the placenta would contain the most highly oxygenated blood.
42
145. Closure of the interventricular foramen with formation of the interventricular membranous
septum results from the fusion of tissue from three sources:
A. coronary sinus, myocardium, and endocardial cushions.
B. left bulbar ridge, right bulbar ridge, and the endocardial cushions.
C. septum primum, septum secundum, and endocardial cushions.
D. septum primum, septum secundum, and myocardium.
E. sinus venarum, crista terminalis, and endocardial cushions.
Notes: Comprehension
Answers A, D, & E are unrelated to the interventricular septum. Ans C is related to septation in the atria.
Ans B, the left and right bulbar ridges and the endocardial cushions compose the interventricular
membranous septum.
146. An 18-year-old female died in a car accident on the way to the hospital for open heart surgery to
correct a septal defect. Autopsy of her heart revealed a patent foramen ovale. There was abnormal
resorption of the septum primum, showing fenestrations with a netlike appearance. Which of the
following best accounts for her anomaly?
A.
B.
C.
D.
E.
Atrioventricular defect
Common atrium
Membranous ventricular septal defect
Muscular ventricular septal defect
Secundum atrial septal defect
Notes: Synthesis
Answers A, C, D are concerned with defects in the ventricles and therefore unrelated to atrial defects.
Answer B concerns absence of the atrial septum (primum and secundum). Answer E is the correct
response.
43
147. An autopsy of an infant demonstrated absence of thymus gland, absence of parathyroid glands,
fish-mouth deformity, low-set notched ears, nasal clefts, thyroid hypoplasia, and cardiac abnormalities.
These anomalies are consistent with abnormal migration of neural crest cells. Which of the following
cardiac structures might also be affected in this infant?
A.
B.
C.
D.
E.
The bundle of His and Purkinje fibers of the heart
The moderator band and septomarginal trabecula of the right ventricle
The pulmonary veins of the left atrium
The sinus venarum, ostium of the coronary sinus, and right atrium
The tricuspid valve, mitral valve, and interventricular membranous septum
Notes: Analysis
Explanation: Answers A-D are all derivatives of cardiogenic lateral plate splanchnic mesoderm. Answer E,
the valves and the interventricular membranous septum are all portions of the cardiac skeleton, which is
neural crest derived.
148. An autopsy of a newborn showed absence of the left subclavian artery. This absent left subclavian
artery probably resulted from abnormal development of which of the following structures?
A. The left fourth aortic arch
B. The left fifth aortic arch
C. The left sixth aortic arch
D. The left seventh intersegmental artery
E. The left eighth intersegmental artery
Notes: Analysis
A - the left fourth aortic arch forms arch of aorta; B - the left fifth aortic arch degenerates; C - the left
sixth aortic arch: distal portion forms ductus arteriosus and the proximal portion forms left pulmonary
artery; D - the left seventh intersegmental artery forms the left subclavian artery; E - the left eighth
intersegmental artery forms superior thoracic artery. D is the correct response.
44
149. Membranous VSD
A. arises from the failure of subendocardial tissue of the endocardial cushions to fuse with the
aorticopulmonary septum and the membranous part of the interventricular septum.
B. in the infant initially causes shunting of blood from the right ventricle to the left ventricle.
C. is a rare condition and the least common type of VSD.
D. is found only in association with an ASD (atrial septal defect), such as patent foramen ovale.
E. results from excessive resorption of myocardial tissue of the muscular part of the
interventricular septum.
Notes: Analysis
Explanation: A – Membranous VSD arises from the failure of subendocardial tissue of the endocardial
cushions to fuse with the aorticopulmonary septum and the membranous part of the interventricular
septum is the correct response; B – Membranous VSD in the infant initially causes shunting of blood
from the right ventricle to the left ventricle is false, initial shunting of blood would be from left ventricle
(higher pressure) to right ventricle (lower pressure); C – Membranous VSD is a rare condition and the
least common type of VSD, false, most common type of VSD, and is the most prominent in males; D –
Membranous VSD is found only in association with an ASD (atrial septal defect), such as patent foramen
ovale, false, can occur without an atrial septal defect; E – Membranous VSD results from excessive
resorption of myocardial tissue of the muscular part of the interventricular septum false, resorption of
myocardial tissue of the muscular part of the interventricular septum would give rise to a muscular VSD.
150. In a normal fetus shortly before birth, which of the following vessel(s) or heart chamber would
contain the most highly-oxygenated blood?
A. Common carotid arteries
B. Ductus arteriosus
C. Pulmonary trunk
D. Right ventricle of the heart
E. Superior vena cava
Notes: Synthesis
Explanation: A – of the five choices, the common carotid arteries contain the most highly oxygenated
blood, and therefore is the correct response; B – within the ductus arteriosus deoxygenated blood is
coming from right ventricle; C – within pulmonary trunk deoxygenated blood coming from lungs to
heart; D – within the right ventricle of the heart there is mixing of deoxygenated blood from superior
vena cava with residual deoxygenated remaining in the right ventricle; E – within the superior vena cava
deoxygenated blood comes from the cranial end of fetus.
45
151. An MRI of an infant shows transposition of the viscera, e.g., situs inversus with dextrocardia: the
liver on the left and the heart on the right. Which of the following conditions would be observed in this
case?
A. The apex of the heart pointing toward the individual's left side
B. The bicuspid valve positioned between the atrium on the left side and the ventricle on the left
side
C. The ostium secundum located in the septum forming part of the wall of the ventricular
chamber on the left side.
D. The pulmonary trunk draining the ventricle on the left side
E. The septum secundum forming part of the wall of the ventricular chamber on the right side
Notes: Synthesis
Explanation: A – The apex of the heart pointing toward the individual's left side is the normal position
for the apex of heart; B – The bicuspid valve positioned between the atrium on the left side and the
ventricle on the left side is the normal position for bicuspid valve; C - The ostium secundum located in
the septum forming part of the wall of the ventricular chamber on the left side is a wrong answer, the
ostium secundum (atrial structure) never forms the ventricular foramen; D – The pulmonary trunk
draining the ventricle on the left side is the correct response, under normal circumstances the
pulmonary trunk would drain the ventricle on the right side; E – The septum secundum forming part of
the wall of the ventricular chamber on the right side is a wrong answer, the septum secundum (atrial
structure) does not form the ventricular septum.
152. Transposition of the great vessels was diagnosed in a male infant with obvious cyanosis and mild
tachypnea. This condition results from which of the following?
A. Abnormal resorption of the septum secundum
B. Abnormal transformation of the sixth pair of aortic arches
C. Failure of the endocardial cushions to fuse
D. Faulty partitioning of the bulbus cordis and the truncus arteriosus
E. Involution of the ductus arteriosus
Notes: Analysis
Transposition of the great vessels occurs with an abnormal partitioning of the outflow tract of the heart
(i.e., bulbous cordis and truncus arteriosus becoming the future aorta and pulmonary trunk). Answers A,
B, C, and E have nothing to do with partitioning of the outflow tract; D – correct response.
46
153. In a particular newborn infant, a substantial volume of blood takes the following route from the
left ventricle to the lower limbs: ascending aorta to brachiocephalic artery to right subclavian artery to
right internal thoracic artery to right 3-12 anterior intercostal arteries to right posterior 3-12 intercostal
arteries to descending aorta. Which of the following conditions does this infant probably have?
A. Abnormal right subclavian artery passing posterior to the esophagus and trachea
B. Coarctation of the aorta distal to the ductus arteriosus
C. Double aortic arch
D. Situs inversus
E. Transposition of the great vessels
Notes: Synthesis
Explanation: M&P, pp. 367 (Fig. 14-41A,B) post-ductal coarctation with collateral circulation to dorsal
aorta: A, C, D, & E are not associated with problem. Postductal coarctation during development of the
embryo/fetus allows collateral circulation to develop in the individual so that structures caudal to the
upper extremities can develop normally and continue to receive blood flow post-partuition, B is the
correct response.
154. Which of the following best describes ductus arteriosus?
A. In the fetus, most of the blood from the pulmonary trunk flows into the aorta.
B. The ductus arteriosus closes just before birth.
C. The ductus arteriosus is a remnant of the left fourth aortic arch.
D. The ductus arteriosus is closed during fetal development.
E. The ductus arteriosus shunts blood from the umbilical vein to the inferior vena cava.
Notes: Comprehension
Explanation: A – In the fetus, most of the blood from the pulmonary trunk flows into the aorta is the
correct response; B – The ductus arteriosus closes just before birth is false, the ductus arteriosus closes
just after birth, not before; C – The ductus arteriosus is a remnant of the left fourth aortic arch is false,
the ductus arteriosus is a remnant of the left sixth distal aortic arch; D – The ductus arteriosus is closed
during fetal development is false, the ductus arteriosus is open during fetal development, to allow blood
to by-pass the lungs thereby allowing their development under a low pressure system; E – The ductus
arteriosus shunts blood from the umbilical vein to the inferior vena cava is false, the ductus venosus
shunts blood from the umbilical vein to the inferior vena cava.
47
155. Which of the following combinations correctly pairs a fetal atrial septum with the opening(s) found
in it?
Septum
A. Septum primum
B. Septum primum
C. Septum secundum
D. Septum secundum
E. Ventricular septum
Opening
foramen ovale
ostium primum and ostium secundum
ostium primum and ostium secundum
ostium secundum
ostium secundum and foramen ovale
Notes: Application
Explanation: A – false, foramen ovale is located in the septum secundum; B – correct response; C – false,
ventricular septum has nothing to do with the atrial openings; D – false, ostium secundum is located in
the septum primum; E – false, ostium primum and ostium secundum are located in the septum primum.
156. In a particular newborn infant, blood from the inferior parts of the body drains into the right
atrium through the azygous and hemiazygous veins and the superior vena cava. The hepatic veins open
separately into the right atrium. Which of the following best accounts for this anomaly?
A.
B.
C.
D.
E.
Absence of hepatic portion of inferior vena cava
Anomalous pulmonary venous connection
Double inferior vena cava
Double superior vena cava
Left superior vena cava
Notes: Synthesis
The problem deals with abnormal drainage from the caudal end of embryo, i.e., there is a shunt from
the caudal end of the embryo to the superior vena cava through the azygous and hemiazygous systems.
This suggests a problem with development of the inferior vena cava. A, absence of hepatic portion of
inferior vena cava, is the correct response. B, anomalous pulmonary venous connection, is false and has
nothing to do with the problem. C, double inferior vena cava, is false, one would have normal drainage
from inferior vena cava on right and drainage through the coronary sinus on left. D & E are both false
since they relate to drainage of the cranial end of the embryo.
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157. Tetralogy of Fallot is a common grouping of four cardiac defects, which consist of the following:
A. common atrium, common ventricle, patent ductus arteriosus, dextrocardia.
B. common outflow tract, membranous ventricular septal defect, patent ductus arteriosus,
patent foramen ovale.
C. hypertrophy of the right ventricle, aortic stenosis, ventricular septal defect, overriding
pulmonary trunk.
D. hypertrophy of the right ventricle, pulmonary stenosis, ventricular septal defect, overriding
aorta.
E. persistent truncus arteriosus, patent ductus arteriosus, hypoplastic left heart syndrome,
common atrium.
Notes: Comprehension
This problem relates to a case in the phase dealing with Tetralogy of Fallot. The problem initially starts
as abnormal partitioning of the outflow track leading to a larger than normal size aorta and a smaller
than normal size pulmonary trunk, reflected in the “over riding aorta and pulmonary stenosis”. Since the
septum between the future aorta and pulmonary trunk is not in the middle, the interventricular
membranous septum fails to form (midline fusion of left and right bulbar ridges with endocardial
cushions), leading to the (high [membranous] VSD) ventricular septal defect. This, in turn, leads to a left
to right shunt of blood causing the right ventricle to hypertrophy. D is the correct response.
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